Mildred Cohn, 96, who overcame gender and religious discrimination to make major advances in biochemistry and who received the nation's most prestigious award in science, died Oct. 12 of pneumonia at a hospital in Philadelphia. She spent many years as a professor at the University of Pennsylvania.

Dr. Cohn, who worked alongside four Nobel Prize-winning scientists early in her career, combined chemistry, biology and physics to become a leader in the emerging sciences of biochemistry and biophysics.

She performed pioneering work in nuclear magnetic resonance, a technology used to examine the structure and metabolism of enzymes and other proteins in chemical reactions. She developed methods, now practiced widely by other scientists, to study metabolic processes at the molecular level.

When she was at Washington University in St. Louis in the 1950s, Dr. Cohn made major advances in identifying the structure of adenosine triphosphate (ATP), a molecule that stores energy for cellular functions. It is considered the universal unit of energy in living cells.

While doing such groundbreaking work, Dr. Cohn was often the only woman working in laboratories filled with men, who sometimes asked her to clean the equipment. In addition to her research, she raised three children and spent more than 20 years struggling for professional recognition before she was invited to join a university faculty.

"My career has been affected at every stage by the fact that I am a woman, beginning with my undergraduate education," she wrote in a 1995 letter quoted by Elga Wasserman in "The Door in the Dream: Conversations With Eminent Women in Science."

Mildred Cohn was born July 12, 1913, in New York and entered the city's Hunter College at 14. She studied chemistry because physics was not offered as a major at Hunter, then a women's college. One of her professors, she said, discouraged her from becoming a chemist because it was not "ladylike."

After graduating from Hunter in 1931, Dr. Cohn received a master's degree in chemistry from Columbia University before she turned 19. At Columbia, she was not allowed to study chemical engineering or become a teaching assistant because those programs were open only to men. While working in the chemistry laboratory of Nobel laureate Harold Urey, Dr. Cohn supported herself as a babysitter.

Leaving graduate school to find work, Dr. Cohn discovered that many jobs in science were restricted to men and Christians. As a Jewish woman, she was doubly disqualified. She spent two years as the only woman among 70 men in Hampton, Va., at the National Advisory Committee for Aeronautics, a forerunner of NASA, before receiving her doctorate in chemistry from Columbia in 1938.

She then worked as an assistant to biochemist Vincent du Vigneaud -- who won a Nobel in 1955 -- first at George Washington University and later at Cornell University's medical school.

In 1946, Dr. Cohn moved to Washington University, where her husband, theoretical physicist Henry Primakoff, had joined the faculty. Dr. Cohn worked in the laboratory of Carl and Gerty Cori, who shared the Nobel Prize for medicine in 1947. (Gerty Cori was the first U.S. woman to receive a Nobel in science.)

Dr. Cohn and Primakoff both went to the University of Pennsylvania in 1960. She retired in 1982 but maintained an office at the university until her death.

In Wasserman's book about female scientists, Dr. Cohn said there were certain advantages to working all those years as a research assistant, rather than as full-fledged faculty member.

"I had no teaching or administrative duty," she said. "I was able to stay home if a child were seriously ill and could spend two months vacationing with my family every summer."

Dr. Cohn was elected to the National Academy of Sciences in 1971 and received the country's highest scientific honor, the National Medal of Science, in 1982. She was the first female president of the American Society for Biochemistry and Molecular Biology and was the first woman on the editorial board of the Journal of Biological Chemistry, which she edited for 10 years.

"My greatest piece of luck," she told Wasserman, "was marrying Henry Primakoff, an excellent scientist who treated me as an intellectual equal and always assumed that I should pursue a scientific career and behaved accordingly."

Her husband, whom she married in 1938, died in 1983. Survivors include three children, Nina Primakoff Rossomando of Westerly, R.I., Paul Primakoff of Davis, Calif., and Laura Primakoff of Rockville; six grandchildren; and four great-grandchildren.